now, peter and adam lanza spent most of their weekends together until 2010. that year was the last time adam lanza saw either his father or his brother, ryan. those who knew adam say he had behavioral issues, needed constant supervision and simply didn't respond to either physical or emotional pain. >> if he had cut himself or hurt himself, he would not know it or feel it. so, we were being very, very careful with him. >> police are still having trouble finding a motive in all of this. a computer, though, taken from adam lanza's home in newtown was badly damaged. investigators also say they found, quote, significant evidence in that house that lanza shared with his mother before killing her. >>> and in light of the tragedy, americans are talking once again about gun control. a new abc news poll found that 54% of americans favor stricter gun control laws. and more than half say the shooting reflects broader problems in our society, not just one troubled person. one leading democratic senator says, this may be the tipping point. but another lawmaker says, more